This application is for a competing renewal of the English Longitudinal Study of Aging (ELSA). We seek partial funding to design and conduct two waves of data collection over a five-year period. We will match this funding with equivalent funding from British sources. ELSA has been modeled on the US Health and Retirement Study, with the important addition of biomedical, performance and psychosocial measures. Its primary objective is to collect longitudinal data on health, disability, economics, and social participation and networks, from a representative sample of the English population aged 50 and older. The value of ELSA is greatly enhanced by our collaboration with the HRS, giving the ability to conduct direct comparisons between the situation of older people in the US and the UK. At the end of the current funding cycle we will have completed two waves of data collection, including biomedical data and in addition to an earlier wave of data collected at a Health Survey for England contact. Over the next five years we will: 1. Design the survey instruments for further waves of data collection, covering economics, social participation and networks, health, functional ability, cognitive function, psychological well-being, and psychosocial risk factors. 2. Continue to test innovations in questionnaire design, sharing innovations with collaborative studies, such as the HRS. 3. Recruit a new cohort of respondents aged 50-54, at wave 3, in order to maintain cross-sectional representativeness and to study social and cross-cohort trends. 4. Interview approximately 11,200 respondents at wave 3 of ELSA and 10,200 respondents at wave 4 of ELSA. 5. Conduct a retrospective life course interview at wave 3 of ELSA in 2006. 6. Collect biomedical and physical performance data from respondents at wave 4 of ELSA in 2008. 7. Construct five waves of accessible and well-documented panel data. 8. Provide these data in a convenient and timely way to the scientific and policy research community. 9. Continue to liaise closely with the HRS and other international studies to maximize the utility of ELSA data.